Uncontrolled practice variability in diagnostic testing has contributed to high rates of error and skyrocketing costs. In the field of oncologic pathology diagnostic testing, more than 70% of patient diagnostic testing samples are defective and an error affects the management of more than 230,000 of the 1.6 million patients diagnosed with cancer annually in the United States. This error frequency has remained unchanged over the last several decades. We believe that simulation based medical education (SBME) combined with Lean methods of quality improvement has the potential to improve cancer diagnostic care by fundamentally changing the underlying culture and processes that contribute to unsafe practices. Within the past year, we initiated the development of an anatomic pathology education-based simulation laboratory (PSL) at the University of Colorado Denver (UCD). The incorporation of simulation training in pathology residency education offers several potential benefits: reduction of patient risk, elimination of practice variability, deliberate practice, development of complex skill sets in an off-line environment, close monitoring of practice with graduated responsibility, practice in environments with simulated failure, and practice with high case volume that include rare and challenging patient specimens specifically prone to error. We hypothesize that anatomic pathology Lean-SBME will replace ineffective and outdated models of training and produce pathologists who are highly skilled, make fewer errors, team-focused and trained in quality improvement. We will perform a single institution, double cohort case-control study by separating residents on the University Hospital anatomic pathology rotation into two groups: 1) an integrated Lean-SBME tract and 2) a traditional apprenticeship tract. We will compare: 1) resident performance outcomes and 2) oncologic pathology patient safety outcomes for the two tracts over a three year interval. We hypothesize that compared to anatomic pathology traditional apprenticeship residents, Lean-SBME residents will perform at higher levels of competence, measured through standardized and validated assessment tools, and the entire post-implementation laboratory will makes fewer errors, measured by standardized quality assurance tools. As a result, patients who have cancer or signs and symptoms suspicious for cancer will receive safer healthcare and will have improved outcomes as a result of improved diagnostic testing services. PUBLIC HEALTH RELEVANCE: The public health relevance of this study primarily lies in the fact that the University of Colorado Hospitals (UCH) serves as one of the major "safe harbor" hospitals in the area;the service population is comprised of 14% of families below poverty level, 30% who do not speak English at home, and 30-40% who are not white. Our goal is to improve the quality of care and patient safety in this population.